I don't stress on oil. Any name brand with a current API or Dexos or Ilsac certification is fine with me. I don't stress on viscosity, although I am well aware CAFE is the tail that wags the dog. I believe one viscosity grade up or down is almost neglible. Won't cause any harm.
Curiosity led me to make an informal observation with my 2019 RAM Classic with the 3.6L Pentastar V6, when I changed the fill from the 5w-20 dealership oil to 5w-30 SuperTech full Syn. After about 380 miles (just one tank) I observed the following from the trucks display:
5w-20 Coolant temp = 201 5w-30 Coolant temp = 197
5w-20 Trans temp = 183 5w-30 Trans temp = 181
5w-20 oil temp = 194 5w-30 oil temp = 194
5w-20 oil pressure = 41 5w-30 oil pressure = 44
5w-20 observed MPG = 21.4 5w-30 observed MPG = 21.2
My conclusion is the truck never noticed bumping up from 5w-20 to 5w-30. I seriously doubt I "lost" 0.2 mpg either, since this is reflective of just one tank (~380 miles) that had less highway crusing than I normally do. FWIW.
Curiosity led me to make an informal observation with my 2019 RAM Classic with the 3.6L Pentastar V6, when I changed the fill from the 5w-20 dealership oil to 5w-30 SuperTech full Syn. After about 380 miles (just one tank) I observed the following from the trucks display:
5w-20 Coolant temp = 201 5w-30 Coolant temp = 197
5w-20 Trans temp = 183 5w-30 Trans temp = 181
5w-20 oil temp = 194 5w-30 oil temp = 194
5w-20 oil pressure = 41 5w-30 oil pressure = 44
5w-20 observed MPG = 21.4 5w-30 observed MPG = 21.2
My conclusion is the truck never noticed bumping up from 5w-20 to 5w-30. I seriously doubt I "lost" 0.2 mpg either, since this is reflective of just one tank (~380 miles) that had less highway crusing than I normally do. FWIW.
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